Field of the Invention
The present inventions relate to methods, apparatus and systems for the delivery of high power laser beams over a distance to a work surface to perform a laser operation or a laser mechanical operation on the work surface, such as, treating, fracturing, tunneling, weakening, welding, annealing, cutting, removing, drilling, penetrating, and combinations and various of these. The work surfaces, for example, may be roads, the earth, bridge supports, dams, ice, rocks, rock faces, pipes, conduit, tubes, columns, wire, cables, girders, beams, buildings, concrete, reinforced concrete, rebar, metal, earth, coal, ore, shale, tar sands, mineral containing materials, steel, tanks, and support structures.
As used herein the term “earth” should be given its broadest possible meaning, and includes, the ground, all natural materials, such as rocks, and artificial materials, such as concrete, that are or may be found in the ground, including without limitation rock layer formations, such as, granite, basalt, sandstone, tar sands, dolomite, sand, salt, limestone, ores, minerals, overburden, marble, rhyolite, quartzite and shale rock.
As used herein, unless specified otherwise, the terms “borehole,” “tunnel,” “shaft” and similar such terms should be given their broadest possible meaning and include any opening that is created in the earth, in a structure (e.g., building, protected military installation, nuclear plant, or ship), in a work surface, or in a structure in the ground, (e.g., foundation, roadway, airstrip, cave or subterranean structure) that is substantially longer than it is wide, such as a well, a tunnel, adit, raise, rise, incline, decline, a hole, a well bore, a mine shaft, a well hole, a micro hole, slimhole and other terms commonly used or known in the arts to define these types of narrow long passages. Such openings may further have segments or sections that have different orientations, they may have straight sections and arcuate sections and combinations thereof; and for example may be of the shapes commonly found when directional drilling is employed or when mining tunnels follow ore deposits, thus incline, decline or maintain a constant gradient, or when road tunnels begin at the surface and extend below a body of water and then return to the surface, such as for example the Chesapeake Bay tunnels. Thus, as used herein unless expressly provided otherwise, the terms “bottom”, “bottom surface” or “end,” “shaft bottom”, “end of tunnel”, “end of decline”, and similar such terms, when used in relation to a borehole, tunnel or shaft, refer to the end of the borehole, tunnel or shaft, e.g, that portion that is farthest along the path from the opening, start, the surface of the earth, other reference point, or the beginning.
As used herein, unless specified otherwise, the terms, “cut,” “cutting,” “sectioning” and similar such terms should be given their broadest possible meaning, and include the remove of material in a pattern that is longer than it is wide, which would include a pattern that is linear, substantially linear, curved, annular, geometric (such as a rectangle, square, trapezoid, etc.) or non-geometric (such as a trace of a natural structure like an ore seam, or other pattern that does not have a common geometric name). A cut may be continuous, such that the material is removed by the laser along the entirely of the pattern, or it may be staggered or partial, which could be viewed as a series of lands (where no material is removed) and cuts (where material is removed), stitches, perforations, spaced holes, etc. The use of the term “completed” cut, and similar such terms, includes severing a material into two sections, i.e., a cut that is all the way through the material, or removing sufficient material to meet the intended objective of the cut. A borehole, a tunnel, a hole, an opening, or any volumetric shape of removed material, may be made using cuts placed adjacent, or substantially adjacent one an another, as for example by delivering the laser beam in a raster scan pattern.
As used herein, unless specified otherwise “offshore” and “offshore drilling activities”, “offshore activities” and similar such terms are used in their broadest sense and would include activities on, or in, any body of water, whether fresh or salt water, whether manmade or naturally occurring, such as for example rivers, lakes, canals, inland seas, oceans, seas, bays and gulfs. As used herein, unless specified otherwise the term “seafloor” is to be given its broadest possible meaning and would include any surface of the earth that lies under, or is at the bottom of, any body of water, whether fresh or salt water, whether manmade or naturally occurring.
As used herein, unless specified otherwise, “mining”, “mine” and similar such terms, are used in their broadest possible sense; and would include all activities, locations and areas where materials of value, e.g., ore, gems, minerals, etc., are removed or obtained from the earth.
As used herein, unless specified otherwise “high power laser energy” means a laser beam having at least about 1 kW (kilowatt) of power. As used herein, unless specified otherwise “great distances” means at least about 500 m (meter). As used herein the term “substantial loss of power,” “substantial power loss” and similar such phrases, mean a loss of power of more than about 3.0 dB/km (decibel/kilometer) for a selected wavelength. As used herein the term “substantial power transmission” means at least about 50% transmittance.
Discussion of Related Art
Mining Activities and Equipment
This is a general background discussion of the mining arts, it being understood that this general discussion does not limit the applicability of the present laser operations, systems and apparatus to the mining arts, presently known, or later developed, including mining arts and practices that may be developed based upon and using the teachings of this specification.
In general, and without limitation, mining and mining activities can generally be categorized into surface mining and underground mining, which may include activities under the surface of the earth and activities under the sea floor. Surface mining may be considered to include activities that take place at or into the surface of the earth to extract deposits of resources, e.g., minerals or ore, which are close, or closer, to the surface. While underground mining may be considered to include activities that take place to obtain deposits of resources that are further below the earth's surface, and thus, require the extraction activities to take place under the surface, i.e., sub-surface, of the earth, including the sea floor.
Surface Mining
In many types of surface mining, heavy equipment, such as an earthmover, first removes the overburden, which is the soil and rock above the resource deposit. Then after the overburden has been removed, generally large machines such as drag lines, dozers, shovels and haulers, extract the ore, e.g., the earth containing the mineral (including various forms of that mineral), such as, gold, silver, iron, argentite, barite, bauxite, chalcocite, hematite, magnetite, taconite, diamonds, coal or salt.
In surface mining to extract the ore, often times, holes are drilled, explosives are placed into the hole and initiated to fracture the rock mass, cut, or otherwise make the ore easier to remove. Following blasting, weakened—fracture rock—material is extracted utilizing mining removal equipment, etc., e.g. excavation and hauling equipment is employed to remove the ore for further processing, if need be, to recover the economic mineral inventory, mineral reserves or resource. In general, surface mining may further be characterized into several types, such as placer mining, strip mining, mountain top removal, hydraulic, open pit, and dredging. In being understood that these characterizations, as well as the general characterizations of surface and underground, are not exclusive, and should be viewed as general characterizations for which some types of activities may come under one or more characterization, and that other terms or names may be used for these, as well as, other activities by those of skill in the art.
Placer mining□ involves types of mining where the resources are deposited in sand or gravel or are otherwise on the surface of the earth, and thus, can be recovered without having to drive, use explosives or any other significant means. This is an older form of mining. The simplest technique of placer gold mining is panning. In panning, some sediment is placed in a large metal pan, combined with an amount of water, and stirred or mixed so that the sand flows over the side. Any gold particles contained in the sand, due to the higher density of gold, will tend to remain on the bottom of the pan after all of the sand and mud has been washed away. The same principle may be employed on a larger scale by constructing a sluice box, with barriers along the bottom to slow the movement of gold particles. This method better suits excavation with shovels or similar implements to feed sediment into the device.
Strip mining is the practice of mining a seam of mineral ore by first removing all of the soil and rock that lies on top of it (the overburden). It is similar to open-pit mining in many regards. Strip mining is a near surface mining method typically used in near surface deposit with low rock strength or hardness. Typically, no drilling and blasting is required in Strip mining, the rock mass is sufficiently weak that ore can be fractured, ripped and excavated through the use of mechanical mining equipment such as bucket wheel excavators, dragline excavator and/or general earth moving equi This method is sometimes referred to as strip mining and/or contour strip mining. Area strip mining may be used on fairly flat terrain to extract deposits over a large area. Contour strip mining may be used in hilly terrain and involves cutting terraces in mountainsides following the contour of the land.
Mountaintop removal, a relatively new form of mining compared to the others described above, involves essentially the restructuring of the earth, e.g., removing the top of a mountain, to reach ores or minerals, as deep as 1,000 feet below the surface.
Hydraulic mining involves high pressure water. The water is sprayed at an area of rock and/or gravel and the water breaks the rock up, dislodging the ore. The water/ore mixture is then further processed.
Open pit mining/Open Cast Mining/Quarry Mining involves the removal of both economic and non-economic near surface material/rock to expose and excavate either economic commodities such as copper, gold, nickel, potash, iron ore, molybdenum, diamonds, coal, oil shale or economic material such as granite, marble or material used for construction i.e. road metal, aggregate, gravel and sand. Typically, open pit mines used to mine material such as granite, marble, gravel sand etc are referred to as a quarry or quarrying etc. Open pit mining will utilize a combination of methods and equipment to remove both the ore and waste (non-economic) material. Initial removal of either the overburden and/or more weathered (weak) rock mass will be removed by mechanical methods as previously described. Generally, rock strength increase with depth as the weathering profile decreases, once the rock strength exceed the mechanical breaking capacity of the machinery, drilling and blasting methods will be used to fracture the rock and subsequently excavate/remove the material/rock using mechanical excavators or shovels. Open Pit mining is non selective and requires the removal of all material ore and waste to the final pit shape, shell or designed economic bottom of the pit. Dredging is a method often used to bring up underwater mineral deposits. Dredging may be used to clear or enlarge waterways for shipping and also may be used to recover underwater minerals
Underground Mining
Underground mining refers to a group of techniques used for the extraction of valuable minerals or other geological materials from the earth Underground or sub-surface mining is a form of where the operations and workings are below ground and is overlain by rock or material strata by definition. Access to the working is via a tunnel or shaft. There are two main components to an underground mine. The access the means by which the underground environment is accessed from the surface and the production (mining) area. There are only two means of accessing an underground mine either vertically via and Shaft—(vertical or inclined typically up 45-55 degrees, sometimes referred to as a raise, rise or whinz) or by a drifting (also referred to as a tunnel, adit, drive, decline, incline, ramp and slope. Drifts can vary in gradient from 0 to +/−30% These access can be developed by either mechanical methods utilizing mechanical cutting, ripping or fracturing or via a drilling and blasting methods, requiring the use of explosives to fracture the rock. Mechanical methods include the utilization of equipment as tunnel boring machine, road header, continuous miner, shaft boring machine and raisebore machine. Drilling and blasting methods require the drilling of blast holes, which are loaded with explosives and initiated (blasted). Several types of drills can be used in drifting, raising and sinking. These include development drills single boom, double boom, triple, boom (often referred to as a development jumbo). There are production drill rigs usually referred to by their brand name i.e. Solo, Cubex these are single drill utilizing for the drilling of larger diameter drill holes. There also small diameter manual drills commonly known as Airleg, Jackleg and stopers. Finally, there are shaft drills, shaft or sinking jumbos
Both types of access can be developed by both mechanical and drill and blast methods, in additions both methods can be applied to, what is typically referred to as soft and hard rock.
Additional terminology refers to the initial access or start of either the drift or shaft. The initial access to a decline, incline or adit is referred to as a portal this is the initial 5-100 meters of the drift, often additional support is required installed to support the potentially more weather material close to the surface. A portal can be initiated either from the original surface (through soil or solid rock) or from a man made surface such as an open pit bottom, wall, bench or a box cut (a large excavation of typically soil-sand-weathered rock material to the start of solid rock, Due to the stability of these material these excavation usually have walls below the minimum rill angle of soil less than 55 degrees), retaining structures may need to be constrain the material.
Similarly the initial entry into a shaft is via the shaft collar from a surface shaft (mines can have internal shafts and raises), typically shaft collar is developed in solid rock. If the shaft location is overlain with significant soil-sand-weather rock this will be excavated until solid rock is reach using earth moving equipment similar to the described box cut. Retaining structures may need to be constructed to retain the material.
In being understood that these characterizations, as well as, the general characterizations of surface and underground, are not exclusive, and should be viewed as general characterizations for which some types of activities may come under one or more characterization, and that other terms or names may be used for these, as well as, other activities by those of skill in the art.
Drift mining is a method of accessing valuable geological material, such as coal, by cutting into the side of the earth, rather than tunneling straight downwards. Drift mines have horizontal entries into the coal seam from a hillside. Drift mines are distinct from slope mines, which have an inclined entrance from the surface to the coal seam. If possible, though, drifts are driven at just a slight incline so that removal of material can be assisted by gravity.
□Slope mining is a method of accessing valuable geological material, such as coal. A sloping access shaft travels downwards towards the coal seam. Slope mines differ from shaft and drift mines, which access resources by tunneling straight down or horizontally, respectively.
Shaft mining is a type of underground mining done by use of a mine shaft. A mine shaft is a vertical passageway used for access to an underground mine. On the surface above the shaft stands complex hoisting, air management, communication and other supply and support equipment.
Hard rock mining is a general term that may be used to refer to various techniques used to mine ore bodies from harder rocks. Thus, it would include an orebody and rock masses that require mining via drilling and blasting mining methods with greater rock strengths these would include orebodies such as gold, silver, iron, copper, zinc tin, nickel, and lead deposits. Hard rock mining techniques may also be used to mine gems, such as diamonds. Soft rock mining is a general term used to refer to orebodies that can be mined using mechanical mining equipment using machines, to fracture, cut or rip the rock. The orebody are typically referred to as been soft rocks such coal, tar sands, and salt, these rock deposits are generally sedimentary It being recognized that these techniques and material may be used in various applications and combinations of applications.
Typical, underground mining methods include, cut and fill mining, room and pillar mining, sub-level caving and block caving and variations of these techniques. These methods can been classified in to two groups caving and non caving methods. The non-caving method the method is designed to either be self supporting (such are room and pillar where pillars of ore are purposely left behind to support the overlying strata) or supported methods where ground support and/or backfill are used to support the overlying strata. These methods include, cut and fill, room and pillar and Long Hole Open stoping, (and variations of these methods such as stope and pillar, vertical crater retreat, benching and shrink stoping).
Caving methods such as sub level caving and block caving (or variations of the method such as inclined caving) the orebody is allowed or purposely.
Mining techniques, may involve the creation of underground “rooms”, where the ore or valuable material has been removed, supported by surrounding pillars of standing rock. Mining techniques can These techniques would include, for example, stope and pillar, room and pillar, long hole stoping, benching, vertical crater retreat, block caving, and sub-level caving.□
□Borehole Mining (BHM) is a remote operated method of mining mineral resources through boreholes by means of high pressure water jets. This process can be carried out from the land surface, open pit floor, underground mine, floating platform, or vessel through pre-drilled boreholes.
Entry under ground and advancement of the shafts or tunnels, to the mining activity, or face of the material to be mined, may be obtained through several ways, including by a declining ramp, an essentially vertical, or vertical shaft, or a essentially horizontal, or horizontal, opening (e.g., an adit).
Thus, for example, a decline may be a spiral tunnel which can go around the deposit and thus circles either the outside or inside of the deposit. The declines can begins with a square or box cut, to function as the portal to the surface. Depending on the amount of overburden and quality of bedrock, a steel or other supports may be required for safety purposes. Shafts are vertical excavations sunk, e.g., bored or dug, into or adjacent to an ore body. Shafts may be sunk for ore bodies where haulage to surface via truck is not economical, or where access to the ore bodies is not practical. Shafts may also be employed in conjunction with a ramp or adits. Adits are horizontal, or substantially horizontal, excavations into the side of a hill or mountain. They are used for horizontal or near-horizontal ore bodies where there is no need for a ramp or shaft, or they may serve to access shafts. An example of a combination of these techniques may be seen when a decline is placed into the side of the pit wall of an surface mine when, for example, the ore is of a payable grade sufficient to support an underground mining operation but the strip ratio (mineral to waste) has become too great to support surface mining operations.
Generally, there underground mining may be viewed as having two principal phases: development mining and production mining. Development mining is composed of excavation almost entirely in (non-valuable) waste rock in order to gain access to the ore or valuable material. Generally, development mining may involve to following activities: remove previously blasted material, scaling (e.g., removing any unstable slabs of rock hanging from the roof and sidewalls to protect workers and equipment from damage), support excavation, drill rock face, load explosives, and blast explosives.
Generally, production mining may be further characterized as, long hole mining methods and short hole mining methods. Short hole mining is similar to development mining, except that it occurs in ore or valuable material. There are several different methods of long hole mining. Such techniques may also be referred to as room & pillar, or cut and fill method. For example, and generally, long hole mining may have two excavations within the ore, or material of value, at different elevations below surface, (e.g, about 15 meters to 30 meters apart), which may also be referred to as long hole stoping or variations off. Holes are then drilled between the two excavations and loaded with explosives. The holes are blasted and the ore is removed from the bottom excavation.
The surrounding walls and roof of the mine excavation area, in general need to be supported by area ground support. Area ground support is used to prevent ground failures and in particular major ground failures. Thus, holes are drilled into the back, e.g., ceiling or roof, and walls of the mine and a long steel shaft, e.g., a rod or rock bolt, is installed to hold the ground together. There are in general three types of these supports: mechanical bolts, grouted bolts, and friction bolts.
Mechanical bolts would include point anchor bolts, e.g., expansion shell bolts. A point anchor bolt is a metal bar between about 20 mm-25 mm in diameter, and between about 1 m to 4 m to 25 m long, this size may vary and is determined to meet the holding and strength requirements for a particular application or mine. There is an expansion unit or assembly at the end of the bolt, which is inserted into the hole. As the bolt is tightened by the installation drill the expansion member, e.g., a shell like assembly, expands and the bolt tightens holding the rock together.
Grouted bolts can be essentially a resin grouted rod, e.g., rebar, and generally can be used in areas that require more support than a point anchor bolt can give. The rebar used may be of similar size as a point anchor bolt but does not have an expansion assembly. Once the hole for the rebar is drilled, cartridges of epoxy resin are installed in the hole. The rebar bolt is installed after the resin and spun by the installation drill. This opens the resin cartridge and mixes it. Grouted bolt types would also include cable bolts, which are used to bind large masses of rock in for example a hanging wall or around large excavations. These cable bolts are much larger than standard rock bolts and rebar, usually between about 10-25 meters. These bolts are grouted with a cement.
Friction bolts, or friction stabilizer, would include bolts of the type solded as SPLIT SET. These bolts can be easier to install than mechanical bolts or grouted bolts; as these bolt are hammered into a drill hole, which has a smaller diameter than the bolt. In this manner as the bold is forced into the hole, pressure from the bolt on the wall holds the rock together. Another type of friction bolt uses a high pressure source, such as high pressure water to expand the bold once it is in place in the rock. An example of this type of bold would be the SWELLEX type bolts and systems.
Other examples of mining methods may include stope and fill, stope and retreat, cut and fill, drift and fill, shrinkage stoping, room and pillar, and block caving. In stope and reteat, material is removed from stope, e.g., a stepped area of excavation, without filling in any voids, allowing the rocks walls to collapse to fill in the extracted area after the ore has been removed. In the stope and fill method, instead of allowing the excavated area to collapse, it is filled with a material; so that room the remaining ore around the first area of excavation can then be removed. Cut and fill mining methods can be used for short hole mining for example in steeply dipping or irregular ore zones, in particular where the hanging wall limits the use of long hole methods. In this method the ore is mined in horizontal or slightly inclined slices, and then filled with waste rock, sand or tailings. Either fill option may be consolidated with concrete, or left unconsolidated. Drift and fill methods are similar to cut and fill techniques, except they may be used in ore zones which are wider. For example, they may include the technique where a first drift is developed in the ore, and is backfilled using consolidated fill. Then a second drift is driven adjacent to the first drift. This carries on until the ore zone is mined out to its full width, at which time this activity is repeated starting atop of the first cut. Shrinkage stoping is a short hole mining method and may find particular suitability for steeply dipping ore zones. This method is similar to, or may be viewed as a variant of, cut and fill mining with the exception that after being blasted, broken ore is left in the stope where it is used to support the surrounding rock and as a platform from which to work. Generally, only enough ore is removed from the stope to allow for drilling and blasting the next slice. The stope is emptied when all of the ore has been blasted. Room and pillar mining is typically done in flat or gently dipping bedded ore bodies. Pillars are left in place in a regular pattern while the rooms are mined out. At some point the pillars may also be taken out starting at the farthest point from the access, allowing the roof to collapse and fill in the stope; allowing for increased ore recovery by not leaving any ore behind in the pillars.
Undergrounds mines can be very deep. For example, it is reported that the TauTona and Savuka gold mines in South Africa are at depths exceeding 12,000 feet, and it is believed that mines will extend to depths of 14,000 feet, 15,000 feet and greater. Other mines may be at least about 5,000 feet, at least about 7,000 feet and at least about 10,000 feet in depth. At these depths the need for, and difficulties in providing electric power and the cables needed to provide such power can be considerable.
Tunneling Activities and Equipment
Tunneling generally relates to the creation of underground passages. Tunnels may be used for roads, rail roads, coal or mineral transportation by for example conveyor systems, for placing communication and power lines, as aqueducts to supply water for consumption or irrigation, as aqueducts for to supply water for hydroelectric stations, and as sewers. Tunnels can be bored or dug in any type of materials varying from soft clay to harder rock. The method of tunnel construction may depend on varied factors such as the ground conditions, the ground water conditions, the length and diameter of the tunnel, the depth of the tunnel, the logistics of supporting the tunnel excavation, the final use, and shape of the tunnel. Examples of the types of tunnel construction would include: cut and cover tunnels, constructed in a shallow trench and then covered over, bored tunnels, constructed in situ, without removing the ground above, which in general may be of circular or horseshoe cross-section; and immersed tube tunnels which would include those that are sunk into a body of water and sit on, or are buried just under, the sea floor of the body of water.
Generally, larger tunnels may be constructed using a tunnel boring machine. These machines can be massive, having diameter of 15 feet, 20 feet, 25 feet or more, and complex having the ability to advance the tunnel face forward while simultaneously placing supports within the tunnel. An example of these large machines were the tunnel boring machines used to dig the “Chunnel” between England and France under the English Channel.
Quarrying Activities and Equipment
Quarrying is a type of surface mining, although quarrying activities can occur underground, that is generally associated with the removal of building and decorative materials such as granite, marble, slate, limestone, sandstone, as well as other types of materials such as aggregate, riprap, sand and gravel. In may applications it is desirable to remove large slaps, or blocks, of such materials for use in building and decorative applications, such as for us on the facade of a building, for a sculpture, or to make counter tops or flooring. In additional to the use of explosives to remove slabs and blocks of the desired materials, large saws are used to cut and section the materials into the desired size.
Road and Infrastructure Repair Activities and Equipment
The repair and replacement of roadways, as well as the repair and replacement of various types of infrastructure, such as steam tunnels, communication tunnels, water lines, electric lines, etc., requires the use of at times large, and very large, and noisy equipment. This equipment and activities can also cause substantial vibrations and potential damage to surrounding structures. This equipment is needed, for example to remove the surface of a roadway so that a new surface could be placed on and bonded to the underlying road, remove the road surface and upper layers of the road bed to all a new road to be built, remove decking from bridges to allow for replacement decking and roadways, remove a highway ramp or bridge structure all together to allow for a new or replacement structure, and to cut holes in existing streets, building or walkways to gain access to other types of infrastructure to among other things repair, replace or enhances that infrastructure. Many times, especially in urban areas, because of the associated noise and vibrations from the use of this equipment the activities have to take place during daylight or business hours when traffic is most heavy. Thus, resulting in the in ability, because of the noise and vibrations, to perform the work in off hours, late in the night when traffic disruption would be at it minimal.